Immediate breast reconstruction post-mastectomy is underutilized and there are significant racial, economic and geographic disparities. This is despite the passing of the Women's Health and Cancer Rights Act (WHCRA), which was signed into law in 1998. WHCRA mandated group health plans, health insurance companies and HMO's to cover breast reconstruction post-mastectomy. Preliminary analyses show that 23 percent of the variation in immediate breast reconstruction is due to between hospital differences and 17 percent is due to between county differences. The hospital and county-level factors that account for this variation have yet to be fully identified. The proposed research is aimed at identifying the hospital and county-level factors that influence the receipt of immediate breast reconstruction post mastectomy, above and beyond individual level factors. Individual-level data from the Nationwide Inpatient Sample (NIS) on ~42,000 women who underwent mastectomy to treat invasive breast cancer or ductal carcinoma in situ (DCIS) will be combined with hospital-level data from the NIS, the American Hospital Association (AHA) and the American Community Survey (ACS) and county-level data from the Area Resource File (ARF). These datasets will provide information on the internal hospital environment (e.g., characteristics of the hospital inpatient population, hospital ownership status) as well as information on the county such as the density of plastic surgeons and socio-demographic characteristics of the county. In addition, the ACS data will be used to develop a geographic information system (GIS) based model of the socio-demographic characteristics of hospital neighborhoods to measure the external hospital environment. A three level generalized linear mixed model (GLMM) will be used to account for the non-independence of patients nested within hospitals and hospitals nested within counties. In this model patients will be the level one unit, hospitals will be the level two unit and counties will be the level three unit. The outcome wll be a binary variable classified by whether the patient received an immediate natural or expander/implant reconstruction or did not receive any type of immediate reconstruction. Accomplishing this research will greatly aid healthcare managers and policymakers in understanding the relative contribution of patient, hospital and county-level factors in the utilization of immediate breast reconstruction post-mastectomy. In addition, the proposed research will inform policymakers about how to reform existing policies, such as WHCRA, in order to increase utilization and eliminate disparities. PUBLIC HEALTH RELEVANCE: This project will determine whether hospital (e.g., the proportion of patients that are non- white, the proportion of patients with public insurance and public ownership status) and county-level factors (e.g., the proportion of residents that live below the poverty level and the proportion of residents with < a high school degree) influence immediate breast reconstruction, independently of individual-level factors. The knowledge gained as a result of this research will inform policy makers about how to refine current healthcare policies such as the Women's Health and Cancer Rights Act, a federal policy implemented in 1998, to improve the access and utilization of breast reconstruction following mastectomy.